Method and system for perceiving a boundary between a first region and a second region of a superabrasive volume

ABSTRACT

Methods of evaluating a superabrasive volume or a superabrasive compact are disclosed. One method may comprise exposing a superabrasive volume to beta particles and detecting a quantity of scattered beta particles. Further, a boundary may be perceived between a first region and a second region of the superabrasive volume in response to detecting the quantity of scattered beta particles. In another embodiment, a boundary between a catalyst-containing region and a catalyst-diminished region of a polycrystalline diamond volume may be perceived. In a further embodiment, a boundary may be perceived between a catalyst-containing region and a catalyst-diminished region of a polycrystalline diamond compact. Additionally, a depth to which a catalyst-diminished region extends within a polycrystalline diamond volume of a polycrystalline diamond compact may be measured in response to detecting a quantity of scattered beta particles. A system configured to evaluate a superabrasive volume is disclosed.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Patent Application No.60/660,138, filed 9 Mar. 2005, the disclosure of which is incorporated,in its entirety, by this reference.

BACKGROUND

Superabrasive compacts are utilized for a variety of applications and ina corresponding variety of mechanical systems. Such superabrasivecompacts may be known in the art as inserts, buttons, machining tools,wear elements, or bearing elements and may be typically manufactured byforming a superabrasive layer on the end of a substrate (e.g., asintered or cemented tungsten carbide substrate). As an example,polycrystalline diamond, or other suitable superabrasive material, suchas cubic boron nitride, may be sintered onto the surface of a cementedcarbide substrate under an ultra-high pressure and ultra-hightemperature (“HPHT”) process to form a superabrasive compact, asdescribed in greater detail below. Polycrystalline diamond elements areused in drilling tools (e.g., inserts, cutting elements, gage trimmers,etc.), machining equipment, bearing apparatuses, wire drawing machinery,and in other mechanical systems. For instance, polycrystalline diamondcompacts (PDCs) have found utility as cutting elements in drill bits(e.g., roller cone drill bits and fixed cutter drill bits).

Explaining further, such PDCs typically include a diamond layer or tableformed by a sintering process employing HPHT conditions that causes thediamond table to become bonded or affixed to a substrate (such ascemented tungsten carbide substrate), as described in greater detailbelow. Optionally, the substrate may be brazed or otherwise joined to anattachment member such as a stud or to a cylindrical backing, ifdesired. Generally, a rotary drill bit may include a plurality ofpolycrystalline abrasive cutting elements affixed to the drill bit body.Each PDC may be employed as a subterranean cutting element mounted to adrill bit either by press-fitting, brazing, or otherwise coupling a studto a recess defined by the drill bit, or by brazing the cutting elementdirectly into a preformed pocket, socket, or other receptacle formed inthe subterranean drill bit. In one example, cutter pockets may be formedin the face of a matrix-type bit comprising tungsten carbide particlesthat are infiltrated or cast with a binder (e.g., a copper-basedbinder), as known in the art. Such subterranean drill bits are typicallyused for rock drilling and for other operations which require highabrasion resistance or wear resistance.

A PDC is normally fabricated by placing a cemented carbide substrateinto a container or cartridge with a layer of diamond crystals or grainspositioned adjacent one surface of a substrate. A number of suchcartridges may be typically loaded into an ultra-high pressure press.The substrates and adjacent diamond crystal layers are then sinteredunder HPHT conditions. The HPHT conditions cause the diamond crystals orgrains to bond to one another to form polycrystalline diamond. Inaddition, as known in the art, a catalyst may be employed forfacilitating formation of polycrystalline diamond. In one example, aso-called “solvent catalyst” may be employed for facilitating theformation of polycrystalline diamond. For example, cobalt, nickel, andiron are among examples of solvent catalysts for forming polycrystallinediamond. In one configuration, during sintering, solvent catalystcomprising the substrate body (e.g., cobalt from a cobalt-cementedtungsten carbide substrate) becomes liquid and sweeps from the regionadjacent to the diamond powder and into the diamond grains. Of course, asolvent catalyst may be mixed with the diamond powder prior tosintering, if desired. Also, as known in the art, such a solventcatalyst may dissolve carbon. Such carbon may be dissolved from thediamond grains or portions of the diamond grains that graphitize due tothe high temperatures of sintering. When the solvent catalyst is cooled,the carbon held in solution may precipitate or otherwise be expelledfrom the solvent catalyst and may facilitate formation of diamond bondsbetween abutting or adjacent diamond grains. Thus, diamond grains becomemutually bonded to form a polycrystalline diamond table upon thesubstrate. A conventional process for forming polycrystalline diamondcutters is disclosed in U.S. Pat. No. 3,745,623 to Wentorf, Jr. et al.,the disclosure of which is incorporated herein, in its entirety, by thisreference. Optionally, another material may replace the solvent catalystthat has been at least partially removed from the polycrystallinediamond.

Solvent catalyst in the polycrystalline diamond may be detrimental. Forinstance, because the solvent catalyst exhibits a much higher thermalexpansion coefficient than the diamond structure, the presence of suchsolvent catalyst within the diamond structure is believed to be a factorleading to premature thermal mechanical damage. Accordingly, as thepolycrystalline diamond reaches temperatures exceeding 400° Celsius, thedifferences in thermal expansion coefficients between the diamond andthe solvent catalyst may cause diamond bonds to fail. Of course, as thetemperature increases, such thermal mechanical damage may be increased.In addition, as the temperature of the polycrystalline diamond layerapproaches 750° Celsius, a different damage mechanism may initiate. Atapproximately 750° Celsius or greater, the solvent catalyst may interactwith the diamond to cause graphitization of the diamond. Suchgraphitization is believed to contribute to or cause mechanical damagewithin the polycrystalline diamond. This phenomenon may be termed “backconversion,” meaning conversion of diamond to graphite. Such conversionfrom diamond to graphite may cause dramatic loss of wear resistance in apolycrystalline diamond compact and may rapidly lead to insert failure.Accordingly, as known in the art, the solvent catalyst in thepolycrystalline diamond layer may be at least partially removed from thepolycrystalline diamond. For instance, the solvent catalyst may be atleast partially removed from the polycrystalline diamond by acidleaching.

Accordingly, a superabrasive volume may include at least two regionswith differing constituents. Thus, it may be advantageous to determineor perceive different regions of a superabrasive volume. For instance,such perception may allow for monitoring of (i.e., quality control)relative to superabrasive apparatus manufacturing and processingmethods. Thus, it would be advantageous to provide methods and systemsfor evaluating (e.g., nondestructively) different regions of asuperabrasive volume.

SUMMARY

The present invention relates generally to observing interaction betweenbeta particles and a superabrasive volume, a superabrasive compact, or asuperabrasive article. More particularly, at least one characteristic ofa superabrasive volume or layer may be determined by detecting scatteredbeta particles. Further, a boundary may be perceived in response todetecting a quantity of scattered beta particles. In one embodiment, asuperabrasive may comprise a polycrystalline diamond. Optionally, acatalyst used for forming the polycrystalline diamond volume may be atleast partially removed from a region of the polycrystalline diamondvolume. In one example, a depth to which a catalyst has been at leastpartially removed from a region of a superabrasive volume (e.g., apolycrystalline diamond volume) may be measured.

One aspect of the present invention relates to a method of evaluating asuperabrasive volume. Particularly, the method may comprise exposing asuperabrasive volume to beta particles and detecting a quantity ofscattered beta particles. Further, a boundary (e.g., at least a portionof a boundary surface) may be perceived between a first region of thesuperabrasive volume and a second region of the superabrasive volume inresponse to detecting the quantity of scattered beta particles.

Another aspect of the present invention relates to a method ofevaluating a polycrystalline diamond volume. Specifically, such a methodmay comprise exposing a polycrystalline diamond volume to beta particlesand detecting a quantity of scattered beta particles. In addition, aboundary may be perceived between a catalyst-containing region of thepolycrystalline diamond volume and a catalyst-diminished region of thepolycrystalline diamond volume in response to detecting the quantity ofscattered beta particles.

A further aspect of the present invention relates to a method ofevaluating a polycrystalline diamond compact. For example, apolycrystalline diamond compact comprising a polycrystalline diamondvolume bonded to a substrate may be provided. In addition, thepolycrystalline diamond volume may be exposed to beta particles and aquantity of scattered beta particles may be detected. Also, a boundarymay be perceived between a catalyst-containing region of thepolycrystalline diamond volume and a catalyst-diminished region of thepolycrystalline diamond volume in response to detecting the quantity ofscattered beta particles.

Another aspect of the present invention relates to a method ofevaluating a polycrystalline diamond compact. Particularly, apolycrystalline diamond compact may be provided, the polycrystallinediamond compact comprising a polycrystalline diamond volume bonded to asubstrate. Also, the polycrystalline diamond volume may be exposed tobeta particles and a quantity of scattered beta particles may bedetected. A depth to which a catalyst-diminished region of thepolycrystalline diamond extends within the polycrystalline diamondvolume may be measured in response to detecting the quantity ofscattered beta particles.

Yet an additional aspect of the present invention relates to a systemconfigured to evaluate a superabrasive volume. For instance, the systemmay comprise a beta particle source, a beta particle detector, andcalibration data or standards for correlating a quantity of detectedbeta particles (e.g., scattered beta particles) to an indicated depth ofa first region of a superabrasive volume.

Features from any of the above mentioned embodiments may be used incombination with one another, without limitation. In addition, otherfeatures and advantages of the instant disclosure will become apparentto those of ordinary skill in the art through consideration of theensuing description, the accompanying drawings, and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features of the subject matter of the instant disclosure, itsnature, and various advantages will be more apparent from the followingdetailed description and the accompanying drawings, which illustratevarious exemplary embodiments, are representations, and are notnecessarily drawn to scale, wherein:

FIG. 1 shows a schematic flow chart of one embodiment of a method ofevaluating a superabrasive volume comprising a first region and a secondregion;

FIG. 2 shows a schematic flow chart of one embodiment of a method ofevaluating a superabrasive volume comprising a catalyst-containingregion and a catalyst-diminished region;

FIG. 3 shows a schematic flow chart of one embodiment of a method ofevaluating a superabrasive volume comprising a cobalt-containing regionand a cobalt-diminished region;

FIG. 4 shows a schematic, cross-sectional view of a beta particleevaluation system during use in evaluating a superabrasive volume;

FIG. 5 shows a schematic flow chart of one embodiment of a method ofevaluating a polycrystalline diamond volume comprising a first regionand a second region;

FIG. 6 shows a schematic flow chart of one embodiment of a method ofevaluating a polycrystalline diamond volume comprising acatalyst-containing region and a catalyst-diminished region;

FIG. 7 shows a schematic flow chart of one embodiment of a method ofevaluating a polycrystalline diamond volume comprising acobalt-containing region and a cobalt-diminished region;

FIG. 8 shows a schematic flow chart of one embodiment of a method ofevaluating a superabrasive compact comprising a superabrasive volumecomprising a first region and a second region;

FIG. 9 shows a schematic, cross-sectional view of a beta particleevaluation system during use in evaluating a superabrasive compact;

FIG. 10 shows a schematic flow chart of one embodiment of a method ofevaluating a superabrasive compact comprising a superabrasive volumecomprising a catalyst-containing region and a catalyst-diminishedregion;

FIG. 11 shows a schematic flow chart of one embodiment of a method ofevaluating a superabrasive compact comprising a superabrasive volumecomprising a cobalt-containing region and a cobalt-diminished region;

FIG. 12 shows a schematic flow chart of one embodiment of a method ofevaluating a polycrystalline diamond compact comprising apolycrystalline diamond volume comprising a first region and a secondregion;

FIG. 13 shows a schematic flow chart of one embodiment of a method ofevaluating a polycrystalline diamond compact comprising apolycrystalline diamond volume comprising a catalyst-containing regionand a catalyst-diminished region;

FIG. 14 shows a schematic flow chart of one embodiment of a method ofevaluating a polycrystalline diamond compact comprising apolycrystalline diamond volume comprising a cobalt-containing region anda cobalt-diminished region;

FIG. 15 shows a schematic, cross-sectional view of a beta particleevaluation system during use in evaluating one embodiment of asuperabrasive compact comprising an arcuate exterior surface;

FIG. 16 shows a schematic, cross-sectional view of a beta particleevaluation system during use in evaluating another embodiment of asuperabrasive compact comprising an arcuate exterior surface;

FIG. 17 shows a schematic, cross-sectional view of a beta particleevaluation system during use in evaluating a boundary between asuperabrasive volume and a substrate; and

FIG. 18 shows a schematic, cross-sectional view of a beta particleevaluation system during use in evaluating a superabrasive layer formedon a base element.

DETAILED DESCRIPTION

Generally, a superabrasive volume may include at least two differentregions. For example, a superabrasive volume may be formed by a HPHTsintering process to include different regions of differing composition.In another embodiment, a superabrasive volume may be formed by a HPHTprocess and may be subsequently treated to remove at least oneconstituent (e.g., a catalyst) from a selected region of thesuperabrasive volume. In yet a further embodiment, a superabrasive layeror volume may be formed by a chemical process (e.g., chemical vapordeposition) or other processes under varying conditions and employingdifferent constituents to form at least two regions within thesuperabrasive layer or volume.

The present invention relates generally to observing interaction betweenbeta particles and a superabrasive volume to perceive a boundary betweentwo regions within the superabrasive volume or between a superabrasivevolume and a substrate. The phrase “beta particles,” as used herein,refers to electrons emitted by unstable atomic nuclei in response toneutron decay (e.g., where a neutron decays into a proton and anelectron). As known in the art, beta particles (which may also bereferred to as beta radiation) may comprise positrons (i.e., so-called“antielectrons” which are identical to electrons but carry a positiveelectrical charge). Accordingly, beta particles are electrons which maybe emitted from radioisotopes. The present invention contemplates thatif beta particles interact with a superabrasive volume, at least some ofthe beta particles may be scattered (e.g., reflected or “backscattered”)generally toward the beta particle source. Such backscattered betaparticles may be measured with a detector (e.g., a Geiger-Mueller tube)and such a measurement may be employed for perception of a boundarybetween a first region of the superabrasive volume and a second regionof a superabrasive volume. The term “superabrasive,” as used herein,refers to any material having a hardness that is at least equal to ahardness of tungsten carbide. For example, polycrystalline diamond andcubic boron nitride are each a superabrasive material.

Accordingly, the present invention contemplates that a system configuredto emit and detect beta particles may be employed for perceiving aboundary between a first region of a superabrasive volume and a secondregion of a superabrasive volume of the superabrasive volume. Moreparticularly, a system configured to emit and detect beta particles maycomprise a beta particle source (e.g., a radioisotope). For example, inone embodiment, a beta particle source may comprise thallium. Betaparticle emission and detection systems are commercially available fromUPA Technology of West Chester Ohio.

For instance, FIG. 1 shows a schematic flow chart of one embodiment of amethod 10 of evaluating a superabrasive volume. More particularly, abeta particle exposure process 20 may comprise exposing a superabrasivevolume to a plurality of beta particles. Further, a beta particledetection process 30 may comprise detecting a quantity of scattered(e.g., backscattered) beta particles. For example, a beta detectionprocess 30 may detect a quantity of scattered beta particles for aselected amount of time during which a superabrasive volume is exposedto beta particles. In addition, in boundary perception process 40, aboundary may be perceived between a first region of the superabrasivevolume and a second region of the superabrasive volume by detecting thequantity of scattered beta particles.

Explaining further, a first region of a superabrasive volume and asecond region of the superabrasive volume may differ in composition.Thus, the boundary may define or delineate the first region and thesecond region. In further detail, a first region and a second region ofa superabrasive volume may include constituents that differ in atomicnumber. For example, a first region of a superabrasive volume mayinclude at least one constituent exhibiting an atomic number thatdiffers by at least about 20% from an atomic number of at least oneconstituent of a second region of a superabrasive volume. Moreparticularly, in one embodiment, a plurality of beta particles may, ingeneral, travel through a first region of a superabrasive volumeexhibiting a relatively lower average atomic number (i.e., a relativelylower density) without significant scattering and may be significantlyscattered by a second region of a superabrasive volume exhibiting arelatively higher average atomic number (i.e., a relatively higherdensity). In one example, a depth of at least one of a first region anda second region of a superabrasive volume may be measured.

In one embodiment, the superabrasive volume may comprise a plurality ofsuper-hard particles or superabrasive grains that are mutually bonded toone another to form a coherent skeleton or matrix structure. Forexample, a superabrasive volume may comprise polycrystalline diamond,cubic boron nitride, or any other superabrasive as known in the art,without limitation. One of ordinary skill in the art will appreciatethat a first region and a second region of a superabrasive volume may beformed by different processes, with different materials, by changing acomposition of at least one of the first and second regions, or bycombinations or variations of the foregoing.

For example, as explained above, a superabrasive volume may be formed byemploying a so-called catalyst, which may facilitate grain-to-grainbonding. Further, subsequent to formation of the superabrasive volume inthe presence of a catalyst, at least a portion of the catalyst may beremoved from a selected region of the coherent skeleton or matrixstructure of the superabrasive volume. Thus, a superabrasive volume maycomprise a catalyst-containing region and a catalyst-diminished region,wherein a boundary is defined between the regions. As shown in FIG. 2,the present invention contemplates a method 10 for evaluating asuperabrasive volume to perceive a boundary between acatalyst-containing region of a superabrasive volume and acatalyst-diminished region of the superabrasive volume. Particularly,such a superabrasive volume may be exposed to a plurality of betaparticles (i.e., in beta particle exposure process 20) and a quantity ofscattered beta particles may be detected (i.e., in beta particledetection process 30). Furthermore, a boundary may be perceived (i.e.,in a boundary perception process 42) between a catalyst-containingregion of the superabrasive volume and a catalyst-diminished region ofthe superabrasive volume in response to detecting the quantity ofscattered beta particles.

In another embodiment, a superabrasive volume may be formed with acatalyst comprising cobalt. Further, a region of the superabrasivevolume may be formed, wherein the region is at least partiallydiminished or depleted of cobalt. Removal of at least a portion ofcobalt from a selected region of the superabrasive volume may beaccomplished by acid leaching, a plating process, another chemicalprocess, or any other process as known in the art. Optionally, a regionof a superabrasive volume may be formed without cobalt (i.e., acatalyst). For example, a first region of a superabrasive volume may beformed via HPHT sintering, while a second region of the superabrasivevolume may be formed by chemical vapor deposition (“CVD”). As shown inFIG. 3, relative to a superabrasive volume that includes at least oneregion comprising cobalt, a method 10 of evaluating a superabrasivevolume to perceive a boundary between a cobalt-containing region of asuperabrasive volume and a cobalt-diminished region of a superabrasivevolume. Particularly, a superabrasive volume may be exposed to aplurality of beta particles in a beta particle exposure process 20 and aquantity of scattered beta particles may be detected in a beta particledetection process 30. In addition, in a boundary perception process 44,a boundary between a cobalt-containing region of the superabrasivevolume and a cobalt-diminished region of the superabrasive volume may beperceived by detecting the quantity of scattered beta particles.

Further, the present invention contemplates that a beta particlegeneration and detection system may be utilized for exposing asuperabrasive volume to beta particles, detecting scattered betaparticles, and perceiving a boundary between a first region of asuperabrasive volume and a second region of a superabrasive volume. Forexample, FIG. 4 shows a schematic, cross-sectional representation of abeta particle evaluation system 100 comprising a beta particle source110, a beta particle detector 130, and an analysis system 150. In oneembodiment, beta particle source 110 may comprise thallium (e.g.,radioisotope thallium 204), although any material that emits betaparticles, as known in the art, may comprise beta particle source 110,without limitation. One of ordinary skill in the art will appreciatethat beta particle source 110 may be selected or tailored so thatemitted beta particles exhibit a desired energy level. Accordingly, thepresent invention contemplates that a suitable beta particle source,relative to a nominal energy level of its emitted beta particles, may beselected so that at least some beta particles interact with ananticipated boundary. In further detail, as shown in FIG. 4, system 100may include a metering port 132 positioned at a selected distancerelative to beta particle source 110. System 100 may be configured sothat beta particles generated by beta particle source 110 are directedtoward aperture 134 of metering port 132. Optionally, emitted betaparticles 111 emitted from beta particle source 110 may be collimated,so that emitted beta particles 111 generally travel within a selected“spot size.” Thus, optionally, emitted beta particles 111 may passthrough metering port 132 without substantial interaction therewith. Inaddition, metering port 132 in combination with coupling structure 136may be configured to inhibit, block, or otherwise interfere withtransmission of scattered (e.g., reflected, backscattered, or otherwiseinfluenced to change direction or velocity) beta particles 112 exceptfor those passing through aperture 134 of metering port 132 in asuitable direction to pass into detector 130 through detector surface133. In one embodiment, beta particle detector 130 may comprise aGeiger-Mueller tube or any other device as known in the art fordetecting beta particles.

In one embodiment, analysis system 150 may comprise a computer or anydevice including at least one processor. Further, at least one inputdevice 151 (e.g., a mouse, a keyboard, etc.) and at least one outputdevice (e.g., a monitor, a printer, a liquid crystal display, etc.) maybe operably coupled to analysis system 150. In addition, analysis system150 may communicate with beta particle detector 130 and may beconfigured to measure a voltage or other signal from beta particledetector 130 to perceive a boundary within a superabrasive volume (e.g.,measure a depth of the boundary from an exterior surface of thesuperabrasive volume). In one embodiment, analysis system 150 may beconfigured to determine a quantity of scattered beta particles 112detected by beta particle detector 130 for a given amount of time.Further, analysis system 150 may be configured to correlate the measuredquantity of scattered beta particles to a depth d between lower surface135 of metering port 132 and a boundary 140 of superabrasive volume 120.As shown in FIG. 4, boundary 140 may comprise a boundary surface betweenregion 116 and region 118. Thus, during operation, lower surface 135 ofmetering port 132 may be positioned at a known distance from uppersurface 121 of superabrasive volume 120. For example, metering port 132may be positioned adjacent to or abutting upper surface 121 ofsuperabrasive volume 120. Further, emitted beta particles 111 may passthrough aperture 134 of metering port 132 and may interact with firstregion 116 of superabrasive volume 120, second region 118 ofsuperabrasive volume 120, or both to perceive boundary 140 (e.g., atleast a portion of a boundary surface) between first region 116 andsecond region 118. In one embodiment, first region 116 of superabrasivevolume 120 may exhibit a density (i.e., an average atomic number) whichis less than a density (i.e., an average atomic number) of second region118 of superabrasive volume 120. Such a configuration may cause emittedbeta particles 111 to interact with the portion of second region 118substantially defining boundary 140. Accordingly, in such aconfiguration, scattered beta particles 112 may travel toward betaparticle detector 130 through aperture 134 of metering port 132. One ofordinary skill in the art will appreciate that as depth d increases,fewer scattered beta particles 112 may be received and detected by betaparticle detector 130.

For example, analysis system 150 may be calibrated by exposing asuperabrasive volume to a plurality of beta particles, detecting aquantity of scattered beta particles, and determining at least onecharacteristic of a boundary by a different or independent method. Inone embodiment, a superabrasive volume may be destructively evaluated todetermine a position or another characteristic (e.g., a size, shape,composition, etc.) of a boundary within a superabrasive volume.Specifically, for example, a superabrasive volume may be analyzed viasystem 100 and then may be sectioned (i.e., cut or otherwise separatedinto pieces) and analyzed to determine a depth d at which the boundaryis positioned. Such a determination may utilize, without limitation,scanning electron microscopy, x-ray diffraction, or any other analyticprocesses as known in the art. The present invention furthercontemplates that a plurality of superabrasive volumes each exhibiting adifferent depth d at which a boundary is positioned may be analyzed viasystem 100 and also analyzed via a different method to developcalibration data which analysis system 150 may employ to determine orpredict a depth d for a given superabrasive volume.

Explaining further, beta particle evaluation system 100 (e.g., analysissystem 150) may comprise a beta particle source 110, a beta particledetector 130, and calibration data for correlating a quantity ofdetected beta particles to an indicated depth of a first region of asuperabrasive volume. In one embodiment, the calibration data maycomprise a first measured quantity of scattered beta particlesassociated with a first depth (e.g., a first depth determined bydestructive evaluation of at least one sample) and at least a secondmeasured quantity of scattered beta particles associated with a seconddepth (e.g., a second depth determined by destructive evaluation of atleast one sample). For example, a first depth may be relatively shallow,while a second depth may be of a magnitude near an anticipated upperlimit. For example, a first depth may be substantially zero (i.e., anexterior surface of a superabrasive volume may be a boundary), or, maybe between about zero and 0.002 inches. As a further example, a seconddepth may be about 0.005 inches. One of ordinary skill in the art willappreciate that a first and/or second depth may be selected inaccordance with a given beta particle source, or vice versa.

In addition, one of ordinary skill in the art will appreciate that oncea first measured or detected quantity of scattered beta particles may becorrelated to the first depth and a second measured or detected quantityof scattered beta particles may be correlated to a second depth.Further, one of ordinary skill in the art will appreciate that linearregression may be employed (via the first measured depth, first measuredquantity of beta particles, the second measured depth, and the secondmeasured quantity of beta particles) to calculate (predict, calculate,or extrapolate) a depth associated with a measured quantity of scatteredbeta particles that differs from the first or second measured quantityof scattered beta particles. Any regression or predictive algorithm asknown in the art may be employed for predicting or calculating a depthof a region of a superabrasive volume based on a detected or measuredquantity of scattered beta particles.

Thus, in one embodiment, calibration data may be designed to correlatethe quantity of detected, scattered beta particles to the indicateddepth of a first region of a polycrystalline diamond volume. In onespecific example, the calibration data may be designed to correlate thequantity of detected, scattered beta particles to the indicated depth ofa catalyst-diminished region of a polycrystalline diamond volume. Inanother example, the calibration data may be designed to correlate thequantity of detected, scattered beta particles to the indicated depth ofa cobalt-diminished region of a polycrystalline diamond volume. One ofordinary skill in the art will appreciate that a beta particle source isa radioisotope will change in its behavior over time (i.e., less betaparticles will be emitted as the radioisotope ages). Therefore, one ofordinary skill in the art will appreciate that calibration should beperformed frequently enough to avoid significant errors.

One of ordinary skill in the art will appreciate that many factors mayinfluence behavior of system 100 during use. For example, the materialcomprising beta particle source 110, the size of metering port 132, thesize and configuration of beta particle detector 130, the shape and/orsize of the boundary, and/or the composition of the superabrasive volumemay influence operational parameters and characteristics of system 100during use. In addition, differences in composition between first region116 and second region 118 of a superabrasive volume 120 may influenceoperational parameters and characteristics of system 100 during use.

In one aspect of the present invention, a superabrasive volume (e.g.,superabrasive volume 120, as shown in FIG. 4) may comprisepolycrystalline diamond. Such polycrystalline diamond may be formed, asdescribed above, by way of a HPHT sintering process. Furthermore, acatalyst may be utilized to form the superabrasive volume, as known inthe art. The present invention contemplates that, as shown in FIG. 5, amethod 12 for evaluating a polycrystalline diamond volume comprising abeta particle exposure process 22, wherein a polycrystalline diamondvolume may be exposed to a plurality of beta particles. In addition, abeta particle detection process 30 may comprise detecting a quantity ofscattered beta particles. Further, a boundary may be perceived, in aboundary perception process 50, between a first region of thepolycrystalline diamond volume and a second region of thepolycrystalline diamond volume by detecting the quantity of scatteredbeta particles.

In another embodiment, as shown in FIG. 6, the present invention furthercontemplates a method 12 for evaluating a polycrystalline diamond volumeincluding a catalyst-containing region and a catalyst-diminished region.Generally, method 12 may comprise a beta particle exposure process 22, abeta particle detection process 30, and a boundary perception process52. For example, catalyst may be at least partially removed from aselected region of a polycrystalline diamond volume by acid leaching,plating processes (e.g., electrolytic or electroless processes), or asotherwise known in the art. More particularly, referring to FIG. 4,region 116 of superabrasive volume 120 may comprise acatalyst-diminished region of a polycrystalline diamond volume. Inaddition, region 118 of superabrasive volume 120 may comprise acatalyst-containing region of a polycrystalline diamond volume.Accordingly, system 100, as shown in FIG. 4, may be utilized forexposing a polycrystalline diamond volume to a plurality of betaparticles (i.e., beta particle exposure process 22, as shown in FIG. 6)and detecting a quantity of scattered beta particles (i.e., betaparticle detection process 30, as shown in FIG. 6). Further, a boundarymay be perceived between the catalyst-containing region of thepolycrystalline diamond volume and a catalyst-diminished region of thepolycrystalline diamond volume in response to detecting the quantity ofscattered beta particles (i.e., boundary perception process 52, as shownin FIG. 6).

In one specific embodiment, a polycrystalline diamond volume may beformed with a catalyst comprising cobalt. Accordingly, as shown in FIG.7, the present invention contemplates a method 12 for evaluating apolycrystalline diamond volume including a cobalt-containing region anda cobalt-diminished region. Particularly, as shown in FIG. 7, thepresent invention contemplates that a polycrystalline diamond volume maybe exposed to a plurality of beta particles in a beta particle exposureprocess 22 and a quantity of scattered beta particles may be detected inbeta particle detection process 30. Furthermore, in a boundary detectionprocess 52, a boundary between a cobalt-containing region of thepolycrystalline diamond volume and a cobalt-diminished region of thepolycrystalline diamond volume may be perceived by detecting thequantity of scattered beta particles. As explained above, perceivingsuch a boundary may comprise measuring a depth to which a catalyst(e.g., cobalt, nickel, iron, etc.) has been at least partially removedfrom a region of the polycrystalline diamond volume.

Another aspect of the present invention relates to evaluating asuperabrasive compact comprising a superabrasive volume bonded to asubstrate. Particularly, FIG. 8 shows a schematic flow chart depicting amethod 14 of evaluating a superabrasive compact. More particularly, asshown in FIG. 8, a superabrasive compact comprising a superabrasivevolume bonded to a substrate may be provided in providing action 21. Inaddition, the superabrasive volume may be exposed to a plurality of betaparticles in a beta particle exposure process 20 and a quantity ofscattered beta particles may be detected in a beta particle detectionprocess 30. Also, a boundary perception process 40 may compriseperceiving a boundary between a first region of the superabrasive volumeand a second region of the superabrasive volume by detecting thequantity of scattered beta particles.

FIG. 9 shows a schematic, side cross-sectional view of a probe 160positioned proximate to a superabrasive compact 190 comprising asuperabrasive volume 120 bonded to a substrate 180 along boundary 182.Accordingly, probe 160 in combination with other components (e.g.,components comprising system 100, as shown in FIG. 4) may be utilizedfor perceiving a boundary 140 between a first region 116 of asuperabrasive volume 120 of a superabrasive compact 190 and a secondregion 118 of the superabrasive volume 120 of a superabrasive compact190, as shown in FIG. 9.

In another embodiment, a boundary between a catalyst-containing regionof the superabrasive volume and a catalyst-diminished region of thesuperabrasive volume may be perceived in response to detecting thequantity of scattered beta particles. More particularly, as shown inFIG. 10, a superabrasive compact comprising a superabrasive volumebonded to a substrate may be provided in providing action 21. Inaddition, the superabrasive volume may be exposed to a plurality of betaparticles in a beta particle exposure process 20 and a quantity ofscattered beta particles may be detected in a beta particle detectionprocess 30. Also, a boundary perception process 42 may compriseperceiving a boundary between a catalyst containing region of thesuperabrasive volume and a catalyst-diminished region of thesuperabrasive volume by detecting the quantity of scattered betaparticles.

In an additional embodiment, as shown in FIG. 11, a boundary between acobalt-containing region of a superabrasive volume and acobalt-diminished region of a superabrasive volume may be perceived bydetecting a quantity of scattered beta particles. As shown in FIG. 11, asuperabrasive compact comprising a superabrasive volume bonded to asubstrate may be provided in providing action 21. In addition, thesuperabrasive volume may be exposed to a plurality of beta particles ina beta particle exposure process 20 and a quantity of scattered betaparticles may be detected in a beta particle detection process 30. Also,a boundary perception process 40 may comprise perceiving a boundarybetween a cobalt-containing region of the superabrasive volume and acobalt-diminished region of the superabrasive volume by detecting thequantity of scattered beta particles.

In yet another aspect of the present invention, a polycrystallinediamond compact comprising a polycrystalline diamond volume bonded to asubstrate may be evaluated by utilizing beta particles. For example,FIG. 12 shows a schematic flow chart depicting a method 16 of evaluationof a polycrystalline diamond compact. Particularly, a polycrystallinediamond compact comprising a polycrystalline diamond volume bonded to asubstrate may be provided, as depicted in providing action 19. Also, thepolycrystalline diamond volume may be exposed to a plurality of betaparticles, as depicted in beta particle exposure process 22, and aquantity of scattered beta particles may be detected, as depicted inbeta particle detection process 30. A perception process 50 may compriseperceiving a boundary between a first region of the polycrystallinediamond volume and a second region of the polycrystalline diamond volumeby detecting the quantity of scattered beta particles.

Optionally, as shown in FIG. 13, a boundary between acatalyst-containing region of the superabrasive volume and acatalyst-diminished region of the superabrasive volume may be perceivedin response to detecting the quantity of scattered beta particles.Specifically, FIG. 13 shows a schematic flow chart depicting a method 16of evaluation of a polycrystalline diamond compact comprising providinga polycrystalline diamond volume bonded to a substrate, as depicted inproviding action 19.

As described above, providing a polycrystalline diamond volume maycomprise providing a polycrystalline diamond volume including a boundarybetween a region of a polycrystalline diamond layer including catalystand a region of the polycrystalline diamond layer from which at least aportion of the catalyst has been removed. For instance, a catalyst(e.g., cobalt, nickel, iron, or any group VIII element, as denoted onthe periodic chart, or any catalyst otherwise known in the art) used forforming the polycrystalline diamond layer may be at least partiallyremoved from the polycrystalline diamond volume. Such a boundary (andassociated region from which a catalyst is at least partially removed)may be formed by immersing (e.g., dipping or otherwise initiatingcontact between) a selected region of the polycrystalline diamond layer20 and a liquid that is formulated to remove at least a portion of thecatalyst. In one embodiment, the catalyst (e.g., cobalt, nickel, iron,etc.) may be substantially completely removed to form a region (e.g., acatalyst-diminished region). For example, as mentioned above, an acidmay be used to leach at least a portion of the catalyst from a selectedregion of polycrystalline diamond volume. As one of ordinary skill inthe art will appreciate, any metals (e.g., tungsten) in addition to thecatalyst may be at least partially removed or substantially completelyremoved as well. The present invention further contemplates thatelectrolytic or electroless chemical processes, or any other processesknown in the art, without limitation, may be employed for removing atleast a portion of a catalyst from a selected region of apolycrystalline diamond layer 20.

As further shown in FIG. 13, the polycrystalline diamond volume may beexposed to a plurality of beta particles, as depicted in beta particleexposure process 22, and a quantity of scattered beta particles may bedetected, as depicted in beta particle detection process 30. Aperception process 50 may comprise perceiving a boundary between acatalyst-containing region of the polycrystalline diamond volume and acatalyst-diminished region of the polycrystalline diamond volume bydetecting the quantity of scattered beta particles.

As a further optional embodiment, as shown in FIG. 14, a boundarybetween a cobalt-containing region of the superabrasive volume and acobalt-diminished region of the superabrasive volume may be perceived inresponse to detecting the quantity of scattered beta particles. FIG. 14shows a schematic flow chart depicting a method 16 of evaluationcomprising providing a polycrystalline diamond volume bonded to asubstrate, as depicted in providing action 19. As described above,providing a polycrystalline diamond volume may comprise providing apolycrystalline diamond volume including a boundary between a region ofa polycrystalline diamond layer including catalyst and a region of thepolycrystalline diamond layer from which at least a portion of thecatalyst has been removed. In addition, the polycrystalline diamondvolume may be exposed to a plurality of beta particles, as depicted inbeta particle exposure process 22, and a quantity of scattered betaparticles may be detected, as depicted in beta particle detectionprocess 30. A perception process 50 may comprise perceiving a boundarybetween a cobalt-containing region of the polycrystalline diamond volumeand a cobalt-diminished region of the polycrystalline diamond volume bydetecting the quantity of scattered beta particles.

As mentioned above, a variety of material-related characteristics aswell as geometry-related aspects may influence the use of beta particlesfor perceiving a boundary within a superabrasive volume. The presentinvention contemplates that any superabrasive volume, superabrasivecompact, or any other superabrasive article may be evaluated byemploying beta particles. For example, the present inventioncontemplates that a superabrasive compact comprising a superabrasivevolume including an arcuate exterior surface may be evaluated byemploying beta particles. Specifically, FIG. 15 shows a schematic, sidecross-sectional view of probe 160 positioned adjacent to superabrasivecompact 191, the superabrasive compact 191 comprising a superabrasivevolume 120 bonded to a substrate 181. Thus, as shown in FIG. 15, a depthd may be measured between an arcuate exterior surface 123 and boundary140. Any of the above-discussed embodiments may be employed forperceiving boundary 140. In addition, any superabrasive compactdisclosed in U.S. application Ser. No. 11/333,969, filed 17 Jan. 2006,the disclosure of which is incorporated, in its entirety, by thisreference, may be evaluated by any method or system disclosed herein.

As shown in FIG. 15, boundary 140 may be substantially planar in oneembodiment. However, the present invention is not so limited. Rather,the present invention contemplates that beta particles may be employedfor perceiving (e.g., measuring, quantifying, or characterizing) anon-planar boundary. For example, FIG. 16 shows a schematic, sidecross-sectional view of a probe 161 positioned proximate to asuperabrasive compact 193 comprising a superabrasive volume 120 bondedto a substrate 181. Accordingly, as shown in FIG. 16, a depth d may bemeasured between an arcuate exterior surface 123 and boundary 140. Anyof the above-discussed embodiments may be employed for perceivingboundary 140.

As one of ordinary skill in the art will appreciate, correlation of aquantity of scattered beta particles to a given depth d of boundary 140from arcuate exterior surface 123 may be different in comparison tocalibration data or algorithms developed for substantially planarboundaries. In addition, FIG. 16 shows a metering port 132 that issmaller than the metering ports shown in FIGS. 4, 9, and 15. Also, asshown in FIG. 16, detector 130 may be sized and configuredadvantageously for a given application. For example, as shown in FIG.16, detector 130 may be larger than the detectors shown in FIGS. 4, 9,and 15 and may also include a detector surface 133 that is at leastpartially arcuate (e.g., concave, convex, etc.). One of ordinary skillin the art will appreciate that calibration data and/or algorithms forperceiving a substantially planar boundary may differ from calibrationdata and/or algorithms for perceiving an arcuate boundary (e.g., atleast a portion of an arcuate boundary surface).

Thus, the present invention contemplates that a beta particle source, ametering port, and a beta particle detector may be tailored for a givenapplication. Additionally, one of ordinary skill in the art willappreciate that more than one boundary formed between adjacent regionsof a superabrasive volume may be perceived or measured by theabove-described methods. For example, different beta particle sources(i.e., beta particle sources emitting particles with different energylevels) may be employed for perceiving a plurality of boundaries locatedat different, respective positions within a superabrasive volume. Manyvariations are contemplated by the present invention.

Another aspect of the present invention relates to perceiving a boundarybetween a superabrasive volume and a substrate. For example, FIG. 17shows a schematic, side cross-sectional view of a probe 160 positionedproximate to a superabrasive compact comprising a superabrasive volume120 bonded to a substrate 180 along boundary 240. In one embodiment,superabrasive volume 120 may comprise a polycrystalline diamond volumefrom which a catalyst (e.g., cobalt, nickel, iron, etc.) may be at leastpartially removed or substantially completely removed. Optionally,substrate 180 may comprise a cemented tungsten carbide material (e.g., acobalt cemented tungsten carbide, any other known cemented tungstencarbide, or any other substrate as known in the art). Thus, betaparticles may be emitted from beta source 110 and may be scatteredthrough interaction with boundary 240. Further, detector 130 may detectscattered beta particles and measurement of a quantity of such scatteredbeta particles may be correlated to a depth d between upper surface 121of superabrasive volume 120 and boundary 240. Any of the above-discussedembodiments may be employed for perceiving boundary 240. As known in theart, boundary 240 may be non-planar, planar, or a combination ofnon-planar and planar features.

In yet a further aspect of the present invention, beta particles may beutilized for perceiving a boundary formed between a superabrasive layerand a base element. For example, FIG. 18 shows a schematic, sidecross-sectional view of a probe 160 positioned adjacent to an article280 comprising a base element 260 and a superabrasive layer 220 formedupon the base element 260. Thus, as explained above, beta particles mayinteract with boundary 240 and may be scattered and detected by detector130 to perceive boundary 240, as described above. Any of theabove-discussed embodiments may be employed for perceiving boundary 240.

One of ordinary skill in the art will understand that any of theabove-discussed methods and systems may provide the ability tonondestructively evaluate a superabrasive volume. Thus, characteristicsof a superabrasive volume that is evaluated via scattered beta particlesmay be substantially unaffected by interaction with beta particles.Thus, such methods and systems may provide advantage over conventionalmethods and systems configured for destructive evaluation ofsuperabrasive volumes. Further, although the methods and systemsdescribed above have been discussed in the context of superabrasivestructures (e.g., comprising polycrystalline diamond), the presentinvention is not so limited, and one of ordinary skill in the art willappreciate that the discussed methods and structures could be used forvaried applications as known in the art, without limitation. Inaddition, while certain embodiments and details have been includedherein for purposes of illustrating aspects of the instant disclosure,it will be apparent to those skilled in the art that various changes inthe systems, apparatuses, and methods disclosed herein may be madewithout departing from the scope of the instant disclosure, which isdefined, at least in part, in the appended claims. The words “including”and “having,” as used herein including the claims, shall have the samemeaning as the word “comprising.”

1. A method of evaluating a superabrasive volume, the method comprising:providing a superabrasive volume comprising a plurality of superabrasivegrains bonded to one another forming a coherent matrix; exposing asuperabrasive volume to beta particles; detecting a quantity ofscattered beta particles; perceiving a boundary between a first regionof the superabrasive volume and a second region of the superabrasivevolume in response to detecting the quantity of scattered beta particleswherein each of the first volume and the second volume include a portionof the coherent matrix, and wherein perceiving the boundary between thefirst region and the second region of the superabrasive volume comprisesperceiving a boundary between a catalyst-containing region and acatalyst-diminished region of the superabrasive volume.
 2. The method ofclaim 1, wherein perceiving the boundary comprises perceiving an arcuateboundary.
 3. The method of claim 1, wherein exposing the superabrasivevolume to beta particles comprises exposing a polycrystalline diamondvolume to beta particles.
 4. The method of claim 3, wherein a catalystused for forming the polycrystalline diamond volume is substantiallyremoved from the first region of the polycrystalline diamond volume. 5.The method of claim 4, wherein perceiving the boundary between the firstregion of the superabrasive volume and the second region of thesuperabrasive volume comprises measuring a depth of the firstsuperabrasive region from an exterior surface of the polycrystallinediamond volume.
 6. The method of claim 4, wherein cobalt issubstantially removed from the first region of the polycrystallinediamond volume.
 7. The method of claim 1, wherein perceiving theboundary between the first region and the second region of thesuperabrasive volume comprises perceiving a boundary between acobalt-containing region and a cobalt-diminished region of thesuperabrasive volume.
 8. A method of evaluating a polycrystallinediamond volume, the method comprising: exposing a polycrystallinediamond volume to beta particles; detecting a quantity of scattered betaparticles; perceiving a boundary between a catalyst-containing region ofthe polycrystalline diamond volume and a catalyst-diminished region ofthe polycrystalline diamond volume in response to detecting the quantityof scattered beta particles.
 9. The method of claim 8, whereinperceiving the boundary comprises perceiving an arcuate boundary. 10.The method of claim 8, wherein perceiving the boundary comprisesmeasuring a depth of the catalyst-diminished region from an exteriorsurface of the polycrystalline diamond volume.
 11. The method of claim8, wherein cobalt is substantially removed from the catalyst-diminishedregion of the polycrystalline diamond volume.
 12. The method of claim 8,wherein perceiving the boundary between the catalyst-diminished regionand the catalyst-containing region of the polycrystalline diamond volumecomprises perceiving a boundary between a cobalt-containing region and acobalt-diminished region of the polycrystalline diamond volume.
 13. Amethod of evaluating a polycrystalline diamond compact, the methodcomprising: providing a polycrystalline diamond compact comprising apolycrystalline diamond volume bonded to a substrate; exposing thepolycrystalline diamond volume to beta particles; detecting a quantityof scattered beta particles; perceiving a boundary between acatalyst-containing region of the polycrystalline diamond volume and acatalyst-diminished region of the polycrystalline diamond volume inresponse to detecting the quantity of scattered beta particles.
 14. Themethod of claim 13, wherein perceiving the boundary comprises perceivingan arcuate boundary.
 15. The method of claim 13, wherein perceiving theboundary between the catalyst-containing region of the polycrystallinediamond volume and the catalyst-diminished region of the polycrystallinediamond volume comprises measuring a depth of the catalyst-diminishedregion from an exterior surface of the polycrystalline diamond volume.16. The method of claim 13, wherein a catalyst used for forming thepolycrystalline diamond volume is substantially removed from thecatalyst-diminished region of the polycrystalline diamond volume. 17.The method of claim 13, wherein cobalt is substantially removed from thecatalyst-diminished region of the polycrystalline diamond volume. 18.The method of claim 13, wherein perceiving the boundary between thecatalyst-containing region and the catalyst-diminished region of thepolycrystalline diamond volume comprises perceiving a boundary between acobalt-containing region and a cobalt-diminished second of thepolycrystalline diamond volume.
 19. A method of evaluating apolycrystalline diamond compact, the method comprising: providing apolycrystalline diamond compact comprising a polycrystalline diamondvolume bonded to a substrate, the polycrystalline diamond volumeincluding a coherent matrix of mutually bonded diamond grains and acatalyst material in a portion of the polycrystalline diamond volume;exposing the polycrystalline diamond volume to beta particles; detectinga quantity of scattered beta particles; measuring a depth to which acatalyst-diminished region of the polycrystalline diamond extends withinthe polycrystalline diamond volume in response to detecting the quantityof scattered beta particles.
 20. The method of claim 19, whereinmeasuring the depth to which the catalyst-diminished region of thepolycrystalline diamond extends within the polycrystalline diamondvolume comprises measuring a depth to which cobalt has been at leastpartially removed from the polycrystalline diamond volume.
 21. A systemconfigured to evaluate a superabrasive volume, the system comprising: abeta particle source; a beta particle detector; calibration data forcorrelating a quantity of detected beta particles to an indicated depthof a first region of a coherent matrix of a superabrasive volume, theindicated depth being less than a total thickness of the coherentmatrix.
 22. The system of claim 21, wherein the calibration datacomprises a first measured quantity of beta particles associated with afirst depth and at least a second measured quantity of beta particlesassociated with a second depth.
 23. The system of claim 21, wherein thecalibration data is designed to correlate the quantity of detected betaparticles to the indicated depth of a first region of a polycrystallinediamond volume.
 24. The system of claim 23, wherein the calibration datais designed to correlate the quantity of detected beta particles to theindicated depth of a catalyst-diminished region of the polycrystallinediamond volume.
 25. The system of claim 23, wherein the calibration datais designed to correlate the quantity of detected beta particles to theindicated depth of a cobalt-diminished region of the polycrystallinediamond volume.